Suppose you have the following system to solve:

$$\{\begin{array}{l}3x+4y-5z=-3.5\\ x-y+z=1.5\\ x-3y+6z=16\end{array}$$

All the equations must be in the form $a\cdot x+b\cdot y+c\cdot z=d$.

1. Press , select Algebra > Solve System of Equations > Solve System of Linear Equation.
2. Enter 3 as the number of equations and fill it as follows:

   

3. We have 3 equations and 3 unknowns ($x$, $y$, and $z$).

   Press . The results should be $x=1$, $y=4$, and $z=4.5$.

Suppose you have to solve the equation $x^3-10x^2+33x-36=0$.

The right-hand side must be 0.

1. Press , select Algebra > Polynomial Tools > Find Roots of Polynomial. Set 3 as the order of the equation. Fill the equation as follows:

   

   The order is the biggest power of $x$ in the equation.

2. Press . The results should be 3 and 4:

   

   $3$ appears twice because $x^3-10x^2+33x-36=(x-3)(x-3)(x-4)$.